A German designer calling himself Seppoman has built a Midibox control system into a sofa. If two people are sitting down, they can output three control values each - left and right buttock weight and how far the person is leaning back. Obviously, the possibilities are pretty much endless. If you've got shares in keyboard manufacturers, sell them now. [More info]. Previously, Seppoman built this incredibly cool rackmounted Commodore 64 SID synth. (Thanks to Tommy and his recently updated website)